The present invention generally relates to a Radio Frequency Identification (RFID) device, and more particularly, to an RFID device which detects and compensates for a temperature measured at a check point so that temperature change in temperature sensitive materials can be traced.
The data processing speed of nonvolatile ferroelectric memory, that is, Ferroelectric Random Access Memory (FeRAM), is typically similar to that of Dynamic Random Access Memory (DRAM). However, FeRAM is different than DRAM, in that data stored in FeRAM is conserved even when the power supply of the memory device is turned off. Thus, FeRAM is quickly gaining publicity and is considered a strong candidate as a next generation memory device.
The structure of FeRAM is similar to that of DRAM in that FeRAM includes a plurality of capacitors. However, the capacitors in a FeRAM device are made of a ferroelectric material having a high residual polarization, which in turn allows for data retention even when the power supplied to the memory device is terminated.
An RFID device stores data within a memory. A typical RFID device includes an analog block, a digital block, and a memory block. The RFID device is operated by a power source which supplies power to the device via transmission received by an antenna of the RFID device. As the distance between the power source and the antenna increases, the power received by the RFID device decreases. As a consequence, it is essential that each circuit of the RFID device have relatively low power consumption.
In RFID tags, temperatures are recorded at check points, and temperature changes are traced during a material moving process in which temperature sensitive materials are being treated. Conventional RFID tags do not include any type of temperature detection within the device, and therefore a separate thermometer is required.
Conventional RFID tags are manufactured using a variety of different processes. As such, even when RFID chips are under the same types of temperature conditions, the RFID chips may have different circuit configurations and different process conditions, so as to have different output voltages. The values used to measure temperature can therefore vary according to the RFID chip characteristics, and thus an RFID chip which can compensate for a temperature measuring value that varies according to the characteristics of the chip is necessary.